1. Field of the Invention
The present invention relates to an apparatus and a method for extracting a single bar from a plurality of bars.
2. Description of the Related Art
In the conventional bar working process, a working is carried out for each of bars. When bars are gathered, it is necessary to extract a single bar from the bars.
The extract of the single bar from the bars has conventionally been carried out by hand or with the use of an apparatus having a complicated mechanism. Japanese Patent Provisional Publication No. S58-43,272 discloses an apparatus, which permits to extract the single bar from the bars (hereinafter referred to as the xe2x80x9cprior art 1xe2x80x9d). In the apparatus of the prior art 1, a holding device has a groove formed in the longitudinal direction of the single bar to be extracted so that only the single bar can be nipped in the groove. A conduit, which is connected to a suction means, communicates with the groove so that only the single bar can be sucked by means of the suction means.
Japanese Utility Model Provisional Publication No. H7-43,427 also discloses an apparatus, which permits to extract a single bar from bars (hereinafter referred to as the xe2x80x9cprior art 2xe2x80x9d). The apparatus of the prior art 2 is provided with (1) a stock on which bars are placed, (2) a sorting table on which a plurality of sorting means are disposed in series and (3) a nipping means for nipping the bar. According to the prior art 2, the single bar is sorted out from the bars and then extracted.
However, in the prior art 1, a suction device serving as the suction means is required to be installed, leading to a complicated and large-scaled structure of the apparatus.
In the prior art 2, a device and a process for sorting the single bar from the bars are required to extract the single bar, leading to a complicated structure of the apparatus and requiring a long period of time for extraction of the single bar.
An object of the present invention, which was made in order to solve the above-mentioned problems, is therefore to provide an apparatus and a method, which permits to extract easily and surely a single bar from bars with the use of a simple mechanism.
In order to attain the aforementioned object, an apparatus of the present invention for extracting a single bar from a plurality of bars, which comprises a holding device for nipping said single bar;
characterized in that:
said holding device comprises nipping members, which face each other and are capable of being opened and closed, said nipping members having a taper space formed therebetween so that only a ""single bar locating in a peak portion of said taper space of a plurality of bars received therein can be nipped.
According to the above-mentioned apparatus of the present invention, it is possible to extract the single bar merely by closing the nipping members to hold the bars between them, thus leading to an extremely simple structure of the apparatus.
The holding device and the plurality of bars may be movable relative to each other so that the holding device can receive the plurality of bars.
According to such a construction, it is possible to close, while detaching the holding device and the bars from each other, the nipping members of the holding device, so as to nip the single bar, permitting an effective extraction of the single bar.
The holding device may comprise a pair of the nipping members, which are swingably connected at a single point with each other.
According to such a construction, it is possible not only to reduce the distance between the nipping members, but also to change an angle between them by closing the nipping members, with the result that the single bar can easily move into the peak portion of the taper space.
The holding device may comprise a pair of the nipping members, which are swingably supported separately from each other.
According to such a construction, it is possible to change an angle formed between the nipping members, with the result that the single bar can easily move into the peak portion of the taper space.
The holding device may comprise a pair of the nipping members, which are disposed so as to linearly move to approach each other.
According to such a construction, there can be formed between the nipping members the taper space in which the single bar can be nipped.
Each of the nipping members may be swingable around a center of its swing motion, locating in a longitudinal one end of the nipping member.
According to such a construction, it is possible to form the taper space between the nipping members in their closing condition, while they are placed in parallel with each other in their opening condition.
The above-mentioned apparatus may further comprise:
a receiver for receiving said plurality of bars, said receiver having opposite ends in a longitudinal direction of said receiver, said holding device being disposed at one of said opposite ends, and the other of said opposite ends having a width longer than said one of said opposite ends.
According to such a construction, it is possible to prevent entanglement of the bars during the steps of nipping the single bar by means of the holding device and separating the single bar from remaining bars, even when there is used bars having a diameter, by which the bars may easily be entangled with each other.
The above-mentioned apparatus may further comprise:
a sensor for obtaining a number and/or diameter of the bar received by said holding device; and
a controller for making, on the basis of an output signal from said sensor, determination whether the number and/or diameter of the bar received by said holding device are correct or not, said controller controlling said holding device to release receipt of the bar and to receive the bar again when the number and/or diameter of the bar is determined to be incorrect.
According to such a construction, it is possible to extract surely the single bar having a prescribed diameter by repeating the nipping step, when the holding device erroneously nip at least two bars or a single bar having an inappropriate diameter different from that of the other bars, which is included therein.
The holding device may be disposed movably.
The holding device may be disposed swingably in the direction perpendicular to the longitudinal direction of the bars.
The holding device may be disposed slidably in the direction perpendicular to the longitudinal direction of the bars.
According to such constructions of the holding device, it is possible to move the single bar nipped by the holding device to a device for carrying out a subsequent step.
The apparatus may further comprise a bar separating and discharging device for separating the single bar nipped by the holding device from remaining bars, and discharging the single bar from the apparatus.
The bar separating and discharging device may comprise a bar separating and discharging member having an inclined portion inclining outward and downward, the bar separating and discharging member being movable from one end of the single bar nipped by the holding device, which is provided at a side of the one end, to the other end thereof, while coming into contact with a lower surface of the single bar.
The bar separating and discharging device may comprise (1) a bar separating device for separating the single bar nipped by the holding device from the remaining bars and (2) a bar discharging device separately provided from the bar separating device, for discharging the single bar; the bar separating device may have a bar separating member, which is movable from one end of the single bar nipped by the holding device, which is provided at a side of the one end, to the other end thereof, while coming into contact with a lower surface of the single bar; and the bar discharging device may have a bar discharging member, which inclines outward and downward, and is swingable.
According to such structures of the bar separating and discharging device, it is possible to surely separate the single bar nipped by the holding device, which may be entangled in the remaining bars, so as to supply the single bar to a device for carrying out a subsequent step.
A method of the present invention for extracting a single bar from a plurality of bars comprises the steps of:
providing a holding device having nipping members, which face each other and are capable of being opened and closed, so that a taper space is formed between said nipping members;
moving one of said holding device and said bars relative to the other of said holding device and said bars so that said bars are received in said taper space; and
closing said nipping members to hold said bars therebetween so as to nip only a single bar locating in a peak portion of said taper space of said bars.
According to the above-mentioned method of the present invention, it is possible to extract the single bar merely by closing the nipping members of the holding device, leading to a simple construction of an apparatus for carrying out the method of the present invention. It is also possible to close, while detaching the holding device and the bars from each other, the nipping members of the holding device, so as to nip the single bar, permitting an effective extraction of the single bar.
The method of the present invention may further comprises the step of providing a sensor for detecting a number or diameter of said bars so that a detection beam for said sensor intersects a locus of a relative movement of said holding device and said bars, thus preventing malfunction of said holding device.
According to such an optional step, it is possible. to nip appropriately the single bar having a prescribed diameter utilizing the sensor, which detects the number or diameter of the bars.
The holding device may be controlled, based on malfunction signals from the sensor, to relieve a nip of the single bar to cause it to fall, and to nip the other single bar again.
According to such control of the holding device, it is possible to extract surely and appropriately the single bar from the bars without causing an incorrect extraction of the bar, even when a bar having a different diameter is included in the bars.
The method of the present invention may further comprises the step of moving the holding device together with the single bar, after a nip thereof.
The above-mentioned moving step of the holding device may comprise causing the holding device to swing in a direction perpendicular to a longitudinal direction of the single bar.
The above-mentioned moving step of the holding device may comprise causing the holding device to slide in a direction perpendicular to a longitudinal direction of the single bar.
According to such optional moving steps, it is possible to move the single bar to a place in which the single bar can easily be supplied to a device for carrying out a subsequent step.
The method of the present invention may further comprise the step of moving, after a nip of the single bar by the holding device, a bar separating and discharging member having an inclined portion inclining outward and downward, from one end of the single bar nipped by the holding device, which is provided at a side of the one end, to the other end thereof, while coming into contact with a lower surface of the single bar, thereby separating and removing the single bar from remaining bars.
The method of the present invention may further comprises the step of (1) moving, after a nip of the single bar by the holding device, a bar separating member from one end of the single bar nipped by the holding device, which is provided at a side of the one end, to the other end thereof, while coming into contact with a lower surface of the single bar, so as to separate the single bar from remaining bars; and then, (2) swinging a bar discharging member having an inclined portion inclining outward and downward to place, while releasing a nip of the single bar by the holding device, the single bar onto the bar discharging member and to move the single bar outward, thereby discharging the single bar from the apparatus.
According to such optional steps, it is possible to surely separate the single bar nipped by the holding device, which may be entangled in the remaining bars, so as to supply the single bar to a device for carrying out a subsequent step.